Question

\(\left(x-7\right)^{30}=\left(x-7\right)^{100}\)

Answer 1

(x-7)³⁰-(x-7)¹⁰⁰ = 0

(x-7)³⁰.[1-(x-7)⁷⁰] = 0

=> x-7 = 0 hoặc 1-(x-7)⁷⁰ = 0

x = 0+7 hoặc x-7 = 1 hoặc x-7 = -1

=> x = 7 hoặc x = 8 hoặc x = 6

Answer 2

\(\Leftrightarrow x-7\in\left\{-1;0;1\right\}\)

\(\Leftrightarrow x\in\left\{6;7;8\right\}\)

Answer 3

=>(x-7)¹⁰⁰-(x-7)³⁰=0

=>(x-7)³⁰ [(x-7)⁷⁰-1]=0

=>x-7=0      =>x=7

hoặc x-7=1   hoặc x=8